It has often been argued that a theory that tries to justify itself fully is either viciously circular or produces an infinite regress of justifications. Thinking that tries to establish ultimate foundations for itself seems in the end to base itself on nothing but its own insistence that it is right. As a result it offers no real knowledge. As Robert Almeder notes, for example, a strong appeal attaches to arguments such as that "there is no non-question-begging way to answer questions such as 'Are you justified in believing your definition of justification?'"
Barris, J. (2007). An internal connection between logic and rhetoric, and a legitimate foundation for knowledge. Philosophy & Rhetoric, 40(4), 353-371.